The term 'twin' is used to describe two people or things that are very SIMILAR in appearance or characteristics. The crossword solutions for this term include 'DUPLICATE' (9 letters), 'LIKENESS' (8 letters), 'SIMILAR' (7 letters), 'MATE' (4 letters), 'BROTHER' (7 letters), 'PAIR' (4 letters), 'COPY' (4 letters), 'CLONE' (5 letters), 'FELLOW' (6 letters), 'DUAL' (4 letters), 'MATCH' (5 letters), 'PEAKS' (5 letters), 'DOUBLE' (6 letters), 'IDENTICAL' (9 letters), 'deadringer' (10 letters), and 'doublenegative' (14 letters). These words all refer to the concept of having two of something that are very SIMILAR, which is the definition of the term 'twin'.